无线 Mesh 网络中多路径路由算法的研究

针对无线 Mesh 网络中传统单径路由协议的不足,提出一种基于动态源路由协议(DSR)的多路径路由算法(IDSR).该算法通过在路由发现过程引入带宽和最大转发次数等限制条件,保证了多条路由请求信息的获取;通过在节点不相交的多径选择过程中引入多 QoS 路由代价函数,有效地实现多路径的选择;通过提供多 QoS 保障,使算法具有较高的求解效率,避免了单径路由的不稳定等特点.实验结果表明,IDSR 算法在无线 Mesh 网络的路由中具有更好的 QoS 性能.     

LTE网络中多目标优化的动态负载均衡算法

小区间动态负载均衡算法的优劣对网络性能有很大的影响,现有算法大都顾此失彼,难以保证网络关键性能指标(如呼叫阻塞率等)达到最佳。为解决这个问题,该文将负载均衡问题建模为多目标优化问题,分别对不同服务质量要求用户建模其相应目标优化函数,对有服务质量要求用户的目标函数是负载均衡指示函数和网络平均负载函数的联合优化函数,而对没有服务质量要求用户(BE用户)的目标函数是所有BE用户吞吐量的总效用函数,并将小区可用资源数和用户服务质量要求作为约束条件。另外,考虑到在实际系统中运行的计算复杂度问题,提出一种复杂度较低的分布式负载均衡算法。包括资源调度策略,用户切换条件和呼叫接入控制。仿真结果表明,该文算法可达到较好的负载均衡效果,能有效降低有服务质量要求用户的呼叫阻塞率,提高网络资源利用率。     

时分波分无源光网络与云无线接入网联合架构中负载平衡的用户关联与资源分配策略

在时分波分无源光网络(TWDM-PON)与云无线接入网(C-RAN)的联合架构中,由于无线域的负载不均衡问题,限制了网络整体的传输效率.为了充分利用TWDM-PON与C-RAN联合架构的网络资源,并保证用户的服务质量(QoS),该文提出一种负载平衡的用户关联与资源分配算法(LBUARA).首先根据不同用户的服务质量需求以及分布式无线射频头端(RRH)的负载对用户的影响,构建用户收益函数.进而,在保证用户服务质量的前提下,根据网络状态建立随机博弈模型,并基于多智能体Q学习提出负载均衡的用户关联和资源分配算法,从而获得最优的用户关联与资源分配方案.仿真结果表明,所提的用户关联和资源分配策略能够实现网络的负载均衡,保证用户的服务质量,并提高网络吞吐量.     

时分波分无源光网络与云无线接入网联合架构中负载平衡的用户关联与资源分配策略

在时分波分无源光网络(TWDM-PON)与云无线接入网(C-RAN)的联合架构中,由于无线域的负载不均衡问题,限制了网络整体的传输效率。为了充分利用TWDM-PON与C-RAN联合架构的网络资源,并保证用户的服务质量(QoS),该文提出一种负载平衡的用户关联与资源分配算法(LBUARA)。首先根据不同用户的服务质量需求以及分布式无线射频头端(RRH)的负载对用户的影响,构建用户收益函数。进而,在保证用户服务质量的前提下,根据网络状态建立随机博弈模型,并基于多智能体Q学习提出负载均衡的用户关联和资源分配算法,从而获得最优的用户关联与资源分配方案。仿真结果表明,所提的用户关联和资源分配策略能够实现网络的负载均衡,保证用户的服务质量,并提高网络吞吐量。     

一种智慧协同网络多参数的多路径路由算法

多路径路由技术采用多条路径同时传输,作为优化资源配置和负载均衡的重要技术,在路由可靠性、QoS路由、传输效率等多方面比单路径传输具有优势.现有互联网网络资源配置和路由机制相对静态和僵化,导致多路径技术的发展存在发展的局限性.现有多路径技术考虑在路由层面不利于多路径路由选择和计算,难以保证传输性能,降低网络传输效率.智慧协同网络能够动态感知网络需求,灵活适配网络资源,更好的支持路由可扩展性.本文在智慧协同网络架构下提出了一种智慧协同网络多参数的多路径路由算法.该算法制定了智慧协同网络多参数的多路径路由协议,对网络性能参数CPU占用率、往返时延(RTT)、带宽进行加权计算得到路径权重值,根据权重值进行流量分配.采用图论理论对网络流量分配及模型进行了分析.并在Mini-Net平台上进行了开发和实验,结果表明,该算法能够优化网络配置,减小往返时延,提高网络吞吐量,从而提高网络性能,实现负载均衡.     

一种新的动态多径路由算法实现MPLS流量优化

提出了一种新的多径路由算法,包括两部分:基于饱和度的平行多路径(SPMP)和基于反馈的负载均衡(FBLB)。在算法中引入了饱和度的概念。新的算法根据实时的负载信息调整流量的传输路径,从而提高了网络资源的利用率,在一定程度上降低了请求的拒绝率和拥塞的发生。     

一种改进的多域光网络保护机制

生存性是保证业务服务质量的关键,多域光网络生存性问题中,由于存在多域间拓扑和路由信息不可见等约束,导致生存性实现较为困难.提出了将多域光网络进行逻辑聚合的思路,在此基础上分别针对域内和域间提出了非等值负载保护和M∶1保护机制.域内的非等值负载保护机制可以根据节点数以及业务量动态地分配保护路径,从而有效地提高资源利用率.     

无线Ad Hoc网络中的QoS路由协议

无线Ad Hoc网络的应用环境以及与Internet的互连都要求其必须提供一定的服务质量(QoS)保证,QoS路由技术是在无线Ad Hoc网络中实现QoS的重要方法。本文对近年来国内外在无线Ad Hoc网络中的QoS路由技术方面取得的研究成果进行了全面的概括总结和分类,对资源预留路由、多径路由和跨层优化路由3类QoS路由协议进行比较分析,并且提出了QoS路由技术亟待解决的问题和今后的发展方向。     

移动自组网络中多径路由的匿名安全

多路径为移动自组网络提供的容错、负载均衡与QoS支持较单路径更有效可行,所以在战术无线自组网等类似系统中采用多径路由策略更能满足系统的实际需求.另外,这类系统对安全性的要求除了基本的通信内容机密、完整与可用等特性外,还要求通信者的身份与位置对敌人保密,为通信者及其使命提供保护.鉴于现有的移动自组网络的匿名路由协议都不是实用的多径路由协议,且未能有效防御被动攻击、拜占庭行为以及匿名的不充分性,本文设计了一种新型安全匿名的多径路由协议,其特点是:在移动自组网络中采用单私钥多公钥密码体制、Bloom Filter与轻型洋葱盲化算法,来实现通信者身份匿名、位置隐藏与路由不可追踪;为源节点提供充分的路由信息,基于充分的信息使用强化学习算法来提高系统抵御被动攻击与拜占庭攻击等路由安全攻击的能力,并增强数据传输的可靠性.通过仿真与分析,显示了算法有较好的性能并达到了所定义的匿名安全要求.     

多业务量矩阵下流量工程算法性能研究

传统域内流量工程TE(traffic engineering)算法中,基于OSPF/IS-IS的TE思想是通过调整链路权重使得全网的负载最均衡.由于Internet的急速发展以及用户业务需求的动态性导致业务量矩阵的不确定性,多业务量下的TE算法研究显得很有必要,而对于多业务量矩阵采取这种算法来最优化网络的研究很少见.本文提出了一种新的启发式基于OSPF/IS-IS链路权重调整的TE算法来解决多业务量矩阵,通过大量仿真实验分析了影响该算法性能的因子,从而为网络规划提供了很好的参考价值.     

VoIP traffic in wireless mesh networks: a MOS‐based routing scheme

Support of Voice over Internet Protocol (VoIP) services in wireless mesh networks requires implementation of efficient policies to support low‐delay data delivery. Multipath routing is typically supported in wireless mesh networks at the network level to provide high fault tolerance and load balancing because links in the proximity of the wireless mesh gateways can be very stressed and overloaded, thus causing scarce performance. As a consequence of using multipath solutions, lower delay and higher throughput can be supported also when a given path is broken because of mobility or bad channel conditions, and alternative routes are available. This can be a relevant improvement especially when assuming that real‐time traffic, such as VoIP, travels into the network. In this paper, we address the problem of Quality of Service (QoS) support in wireless mesh networks and propose a multipath routing strategy that exploits the Mean Opinion Score (MOS) metric to select the most suitable paths for supporting VoIP applications and performing adaptive load balancing among the available paths to equalize network traffic. Performance results assess the effectiveness of the proposed approach when compared with other existing methodologies. Copyright © 2015 John Wiley & Sons, Ltd.     

An Ant-based Multipath Routing Algorithm for QoS Aware Mobile Ad-hoc Networks

In the wireless ad-hoc network management, Quality of Service (QoS) is an important issue. Along with the QoS ensuring, another desirable property is the network reliability. In data communications, multi-path routing strategy can cope with the problem of traffic overloads while balancing the network resource consumption. In this paper, we propose a new multipath routing algorithm for QoS-sensitive multimedia services. Based on the ant colony optimization technique, the proposed algorithm can establish effective multi-paths to enhance the network reliability. According to the load balancing strategy, data packets are adaptively distributed through the established paths while maintaining an acceptable level of QoS requirement. The most important feature of the proposed approach is its adaptability to current traffic conditions. Simulation results indicate the superior performance of the proposed algorithm, while other schemes cannot offer such an attractive performance balance.     

Improved multipath routing with WNN for the open networks

Multipath routing mechanism is vital for reliable packet delivery, load balance, and flexibility in the open network because its topology is dynamic and the nodes have limited capability. This article proposes a new multipath switch approach based on traffic prediction according to some characteristics of open networks. We use wavelet neural network (WNN) to predict the node traffic because the method has not only good approximation property of wavelet, but also self-learning adaptive quality of neural network. When the traffic prediction indicates that the primary path is a failure, the alternate path will be occupied promptly according to the switch strategy, which can save time for the switch in advance. The simulation results show that the presented traffic prediction model has better prediction accuracy; and the approach based on the above model can balance network load, prolong network lifetime, and decrease the overall energy consumption of the network.     

Multipath Cognitive Routing in Integrated Multicast Satellite-HAP System Structures

A new multilayered inter satellite-high altitude platform(HAP)system routing algorithm is proposed,which is mainly based on multipath routing to ensure the network reliability.The proposed multipath routing scheme principally relies on splitting the traffic between different paths to make the best utilization of multiple routes.Linear programming is the main method used for multipath selection.The major constraints to the quality of service(QoS)(delay and link utilization)have been taken into account to meet the criteria of the advanced multimedia applications.Due to the effect of link utilization,the system encounters traffic flow oscillation between paths over time,which affects the system performance.Hence,to fix this issue,we propose a cognitive routing algorithm which reacts to the long-term changes of the traffic loads rather than short-term ones.The performance of the proposed routing techniques has been evaluated using appropriate simulation models and implemented by Matlab.     

Delay constraint multipath routing for wireless multimedia ad hoc networks

According to the disadvantages of real time and continuity for multimedia services in ad hoc networks, a delay constraint multipath routing protocol for wireless multimedia ad hoc networks, which can satisfy quality of service (QoS) requirement (QoS multipath optimized link state routing [MOLSR]), is proposed. The protocol firstly detects and analyzes the link delay among the nodes and collects the delay information as the routing metric by HELLO message and topology control message. Then, through using the improved multipath Dijkstra algorithm for path selection, the protocol can gain the minimum delay path from the source node to the other nodes. Finally, when the route is launched, several node‐disjoint or link‐disjoint multipaths will be built through the route computation. The simulation and test results show that QoS‐MOLSR is suitable for large and dense networks with heavy traffic. It can improve the real time and reliability for multimedia transmission in wireless multimedia ad hoc networks. The average end‐to‐end delay of QoS‐MOLSR is four times less than the optimized link state routing. Copyright © 2014 John Wiley & Sons, Ltd.     

QoS路由度量参数的选择问题研究

具有服务质量保证的QoS路由技术是为具有QoS要求的多媒体等网络业务提供有保证的网络服务的核心要素。QoS路由技术由路由选择算法以及用于反映网络状态的路由度量参数的选择、获取与更新两部分内容组成。正确选取合适的度量参数是减小寻路开销，得到简单、具有扩展性的选路算法并获得满足业务要求的QoS路由的前提与基础。本对QoS路由所需要的度量参数的基本性质、选取方法等问题进行了较全面的分析讨论，并简要介绍了度量信息更新的基本策略。     

Performance of Adaptive Routing in Wavelength-Routed Networks with Wavelength Conversion Capability

This paper concerns itself with the performance of adaptive routing in wavelength-routed networks with wavelength conversion capability. Exploiting the concept of load balancing, we propose an adaptive weighted-shortest-cost-path (WSCP) routing strategy. The salient feature of WSCP is that it seeks the path that minimizes the resource cost while simultaneously maintaining the traffic load among the links as balanced as possible. In our simulation, we compare the blocking probability, average hops and link utilization of WSCP with traditional shortest-cost-path (SCP) strategy, fixed routing and alternate routing. The numerical results show that WSCP can enhance blocking performance and just lengthen hop distances a little longer. The improvement is more significant in denser networks or with more wavelengths. We also develop an analytical model to estimate blocking performance of WSCP and compare analyses with simulations. Because of the benefit from load balancing, the proposed WSCP strategy can be used as a path selection algorithm in traffic engineering.     

A hierarchical multilayer QoS routing system with dynamic SLAmanagement

This paper proposes a hierarchical multilayer QoS routing system with dynamic SLA management for large-scale IP networks. Previously, the promising approach to provide QoS in large-scale IP networks using a mixture of DiffServ-based QoS management and MPLS-based traffic engineering has been actively discussed. However, the introduction of QoS exacerbates the already existing scalability problems of the standard IP routing protocols. In order to address this issue, we propose a new scalable routing framework based on hierarchical QoS-aware path computation. We augment the existing OSPF and CR-LDP protocols to support hierarchical QoS routing, QoS aggregation, and QoS reservation in our MPLS-DiffServ-based hierarchical routing network. In order to provide additional flexibility and cost-efficiency, we augment the network with a policy server which is capable of dynamically handling SLAs between the networks and providing load balancing management within the network. We implement a prototype of the proposed framework and study its performance with a virtual network simulator and specially designed QoS routing algorithm simulator. In our simulations, we evaluate both the implementation complexity and algorithms performance; the results demonstrate the efficiency of the framework and its advantages over the existing proposals     

分布式服务质量路由预计算算法

服务质量路由作为下一代IP互联网提供服务质量(QoS)控制的一种重要方案,如何提高其可扩展性和路由性能是有待解决的难题.本文提出了基于聚类的分布式预计算算法,以具有多种QoS参数的路由表预计算为目标,引入了支持QoS参数的扩展距离向量,通过网络中各个节点的分布式协同计算,大大降低了单个路由器的计算复杂度.文章分析了优势路径及其选取策略,给出了路由计算中优势路径聚集的聚类方法,实现了QoS路由表的高效聚集压缩.实验结果进一步验证了该算法具有计算量小和QoS路由性能高的优点,在QoS度量维数和网络规模方面均具有良好的可扩展性,并对域间算法研究提供了重要依据.